The Coordinating Core is made up of four interacting components. Administrative Unit: overall responsibility for coordinating Center activities with input from the ET, including communications, resource management, evaluation, and insuring compliance with institutional and Federal policies;Data Management and Information Svstems Unit: manages all Center-related data to insure seamless interaction among cores and affiliated research projects;supports the HNRC website and videoconferencing;Statistics Unit: consults with investigators during all study stages, from design to final analyses;also provides ad hoc consultation;Participant Accrual and Retention (PAR) Unit: Recruits and retains participants for specific studies, and maintains the HNRC cohort so it is accessible to investigators to jump start new projects. Since these four components, which might ordinarily be separate cores, are part of one coherent core, we ran into space limitations given the 10-page limit per core. Previously, Dr. Dianne Rausch (NIMH) authorized a 3-page Addendum for each of the Units. This Addendum (section 17) can be found following item "16. Resource Sharing". Also included in the Addendum is a listing of the projects that have utilized the various Units ofthe Coordinating Core.